抑制白血病K562细胞FoxM1表达可增强细胞对高三尖杉酯碱的敏感性

目的:探讨抑制白血病K562细胞叉头框蛋白M1(Fox M1)是否增强细胞对高三尖杉酯碱(HHT)的敏感性。方法:HHT以不同浓度(0、0.015、0.030和0.045μmol/L)和最低起效浓度不同时间(0.015μmol/L,0、24、48和72 h)作用于K562细胞,real-time PCR和Western blot检测Fox M1 mRNA和蛋白表达;以0.015μmol/L HHT作用K562细胞后转染Fox M1 siRNA,观察沉默K562细胞Fox M1后细胞对HHT的敏感性、细胞增殖和凋亡效应以及Fox M1相关靶分子c-Myc和Sp1表达状况。结果:随着HHT浓度增加和时间延长Fox M1表达逐渐降低,说明HHT抑制K562细胞Fox M1表达;HHT处理K562细胞后转染Fox M1 siRNA,细胞生长和克隆形成显著下降,细胞凋亡增加,因此抑制Fox M1可增加K562细胞对HHT的敏感性;Fox M1 siRNA组c-Myc和Sp1表达显著降低,表明Fox M1可正性调控c-Myc和Sp1表达。结论:HHT可以抑制白血病K562细胞Fox M1表达,干扰Fox M1可增强细胞对HHT的敏感性。     

Superior visible light photocatalytic performance of reticular BiVO4 synthesized via a modified sol–gel method

Reticular BiVO₄ catalysts were successfully synthesized via a modified sol–gel method. Here, citric acid (CA) was used as the chelating agent and ethylenediaminetetraacetic acid (EDTA) was used as the chelating agent and template. Furthermore, the effects of pH values and EDTA on the structure and morphology of the samples were studied. We determined that EDTA and pH played important roles in the determination of the morphology of the as-prepared BiVO₄ samples. Photocatalytic evaluation revealed that the reticular BiVO₄ exhibited superior photocatalytic performance characteristics for the degradation of methylene blue (MB) under visible-light (λ > 400 nm) exposure, about 98% of the MB was found to degrade within 50 min. Moreover, the degradation kinetics of MB was in good agreement with pseudo-first-order kinetics. The obtained apparent reaction rate constant k_app of reticular BiVO₄ was much higher than that of BiVO₄ synthesized by the citric acid sol–gel method.

Reticular BiVO₄ catalysts with superior visible light photocatalytic performance were successfully synthesized via a modified sol–gel method.     

内镜下多环黏膜套扎切除术治疗食管癌前病变和食管早癌的疗效及安全性分析*

目的探讨内镜下多环黏膜套扎切除术(EMBM)治疗食管癌前病变和食管早癌的疗效及其安全性。方法回顾性分析2013年1月-2016年6月在该院内镜中心接受EMBM治疗的75例食管癌前病变和食管早癌患者,观察记录手术时间、手术并发症和治疗效果,对比术前和术后病理结果,并结合随访结果,分析总结EMBM的疗效。结果 75例患者均顺利完成EMBM术,手术时间(40.00±9.21)min,3例术中并发出血,均成功内镜下止血,无穿孔、迟发性出血和操作相关死亡发生。9例患者术后出现食管创面狭窄,予以内镜下球囊扩张后狭窄缓解。EMBM术后病理:低级别上皮内瘤变(LGIN)24处,高级别上皮内瘤变(HGIN)45处,黏膜内癌(IMCA)9处,所有患者水平切缘均阴性。相比较EMBM前的钳夹活检,有21处(26.9%)标本病理结果发生变化。随访期间,2例患者术后半年、4例患者术后1年复发,再次给予内镜成功治疗。其余患者随访期间未见复发。结论 EMBM具有操作简单、用时短和并发症少特点,是治疗食管早癌、尤其是食管癌前病变安全有效的方法。     

Zn/Al层状双氢氧化物-聚氯乙烯纳米复合物的制备与性能

用共沉淀法制备油酸钾改性的Zn2+、Al3+层状双氢氧化物（Zn/Al-LDH）,以环己酮为溶剂,用溶液插层法制备了Zn/Al层状双氢氧化物-聚氯乙烯(PVC)纳米复合物。采用傅里叶红外（FT-IR）、X-射线衍射（XRD）、透射电镜(TEM)对复合材料的结构及形貌进行了表征,并用热分析仪、万能试验机和紫外分光光度计研究了复合物的热稳定性能、拉伸性能和紫外吸收性能。结果表明：Zn/Al-LDH纳米片层无序分散在PVC基体中;Zn/Al-LDH对PVC低温时的骨干脱氯化氢有促进作用;与PVC膜相比,复合膜的分解温度降低,高温碳化温度升高,复合膜的拉伸强度及断裂伸长率得到提高,在300~380 nm具有一定的紫外吸收性能。     

阿霉素化学键接聚合物纳米颗粒的合成及pH敏感释放

合成了前驱体三-(2-氨乙基)-N,N',N"-三硫辛酸氨,该前驱体经三丁基膦(TBUP)还原后得到末端带有6个巯基的小分子单体(C-6SH)并共价偶联腙键修饰的阿霉素-(6-马来酰亚胺基己酰)腙(MAL-DOX)。通过巯基与丙烯酸酯的点击化学反应,以二甲基丙烯酸乙二醇酯(EGDMA)为交联剂,连续投料制备了具有内核交联、表面聚乙二醇(PEG)化与pH敏感药物释放特性的聚合物纳米颗粒。采用动态光散射粒径分析(DLS)和透射电镜(TEM)对纳米颗粒的尺寸和形貌进行表征,结果表明该纳米颗粒呈球形,平均尺寸为42 nm。体外药物释放表明:通过腙键连接阿霉素(DOX)的聚合物纳米颗粒具有良好的pH响应性释放能力,即在酸性条件下(pH=5.5)的释放速率比生理pH环境下要明显加快。     

Heteroatom-doped nanoporous carbon from recyclable Pueraria lobata and its dual activities for oxygen reduction and hydrogen evolution reactions

Many efficient and non-precious metal catalysts for oxygen reduction or hydrogen evolution reactions have been developed, but bifunctional catalysts for both oxygen reduction reaction and hydrogen evolution reactions are seldom reported despite their advantages. Herein, we designed the bulk preparation of heteroatom-doped nanoporous carbon catalysts using widely available and recyclable Pueraria lobata powder as the carbon source. The typical product was N, P and Fe Tri-doped nano-porous carbon (N,P,Fe-NPC) with high surface area (BET surface area of 776.68 m² g⁻¹ and electrochemical surface area of 55.0 mF cm⁻²). The typical N,P,Fe-NPC sample simultaneously exhibited high activities for oxygen reduction and hydrogen evolution reactions. Because of the high surface area and the tri-doping of N, P and Fe elements, the prepared material may have applications in other fields such as gas uptake, sensors, sewage treatment, and supercapacitors. The suggested approach is low-cost, simple and readily scalable.

The bulk preparation of an N, P and Fe Tri-doped nano-porous carbon sample using recyclable Pueraria powder, which exhibits dual activities.     

应用医院感染实时监控系统降低医院感染漏报率

目的评价医院感染信息化对降低医院感染漏报率的效果。方法 2012年前某院医院感染监测一直采用传统监测方法,2012年开始应用医院感染实时监控系统,调查2011—2013年每年7—12月医院感染病例,比较医院感染实时监控系统应用前后漏报率。结果 2011—2013年每年7—12月医院感染漏报率分别为12.12%、8.16%、4.55%,3年同期医院感染漏报率比较,差异有统计学意义(χ2=8.02,P0.05)。结论医院感染信息化管理方式可有效降低医院感染漏报率。     

Applicability of the one-step DVS method for the determination of amorphous amounts for further different hydrophilic and hydrophobic drugs

In a former publication the authors showed that low amounts of amorphous content (LOQ of 0.5%) in a hydrophobic model API (Ciclesonide) can be measured with an individually adjusted one-step dynamic organic vapor sorption (DVS). In this investigation the applicability is tested on various APIs which differ in lipophilicity (poor water solubility) and hygroscopicity (absorption of water).The vapor sorption method proved to be applicable in almost all cases. Moisture sorption isotherms were determined for all five investigated crystalline and amorphous APIs. However, it was necessary to select the parameters individually for each API. The used solvents (water, methanol, isopropanol and methylene chloride) and the humidity-levels (0.05 p/p₀ until 0.5 p/p₀) were chosen carefully because otherwise the amorphous amounts switch to their crystalline counterparts and are not detectable. The production of fully amorphous samples (absence of crystalline material measured by DSC, mDSC and XRPD) was optimized over several trials. As successfully methods proved ball-milling, freeze-drying, spray-drying and/or quench cooling. In the next step these fully amorphous amounts were blended with crystalline starting material to calibration curves (Turbula blender, influence of electrostatic charge to homogeneity) for the calculation of amorphous content.In summary, the following presented methods were used to determine and quantify low amorphous amounts (between 1.5% and 17.0%) in jet-milled powders (grinding pressure of 8 bar, 1–3 grinding cycles), respectively.     

The involvement of TRPV4 on the hypoxia-induced oxidative neurotoxicity and apoptosis in a neuronal cell line: Protective role of melatonin

The hypoxia (HYPX)-mediated excessive generation of mitochondrial free reactive oxygen species (mROS) and the overload Ca²⁺ influx via the inhibition of TRPV4 are controlled by the treatment of antioxidants. However, the molecular mechanisms underlying melatonin (MLT)'s neuroprotection remains elusive. We investigated the role of MLT via modulation of TRPV4 on oxidative neurodegeneration and death in SH-SY5Y neuronal cells. The SH-SY5Y cells were divided into five groups as follows: control, MLT (1 mM for 2 h), HYPX (200 μM CoCl₂ for 24 h), HYPX + MLT, and HYPX + TRPV4 blockers (ruthenium red-1 μM for 30 min). The HYPX caused to the increase of TRPV4 current density and overload Ca²⁺ influx with an increase of mitochondrial membrane potential and mROS generation. The changes were not observed in the absence of TRPV4. When HYPX exposure and TRPV4 agonist (GSK1016790A)-induced TRPV4 activity were inhibited by the treatment of ruthenium red or MLT, the increase of mROS, lipid peroxidation, apoptosis, Zn²⁺ concentrations, TRPV4, caspase -3, caspase -9, Bax, and Bcl-2 expressions were restored via upregulation of reduced glutathione, glutathione peroxidase, and total antioxidant status. The levels of apoptosis and cell death in the cells were enriched with increases of caspase -3 and -9 activations, although they were decreased by MLT treatment. In conclusion, the treatment of MLT modulates HYPX-mediated mROS, apoptosis, and TRPV4-mediated overload Ca²⁺ influx and may provide an avenue for protecting HYPX-mediated neurological diseases associated with the increase of mROS, Ca²⁺, and Zn²⁺ concentration.